CONSTANT LIFE FATIGUE DIAGRAM WITH SMOOTH SPECIMENS FOR STRUCTURAL STEEL

The constant life fatigue curve equation for structural steel smooth specimens is presented. Based on the equation, the article presents a new method by which constant life fatigue diagram of structural steel smooth specimens can be obtained, so long as material data for S-N curve of symmetry cycle (r = -1) are determined. When compared to traditional method, constant life fatigue diagram based on constant life fatigue curve equation can reduce fatigue tests by 60%～70%.